Validity of the international physical activity questionnaire (IPAQ-s) as a measure of physical activity in people with multiple sclerosis. (January 2019) - Fortune, J.; Norris, M.; Stennett, A.M.; Kilbride, C.; Lavelle, G.; Hendrie, W.; DeSouza, L.; Victor, C.; Abdul, M.; Ayokye, N.; Ryan, J.M.